Railway safety is a very complicated subject, which is determined by numerous aspects. In Hong Kong, with increasing patronage and traffic density of MTR Railway System, public attention is focused much more on the rail integrity. This paper proposed an automatic RFID detection based railway identification system (RVI) to give the risk assessment to the rail. In the RVI system, RFID detection is applied. In addition, Monte Carlo analysis is applied to select the best position for RFID tags. A trial has considered simulated situation of Hong Kong MTR. The trail involved 8 scenarios, which achieved 89% detection success rate. RVI system helps to enhance the reliability, accuracy and efficiency of remote condition monitoring of rail integrity.